A couple of quick comments, based on recent discussions:
1) Some people in the US are using the term "aircard" (Sierra Wireless' brand) as a generic term for 3G/WiMAX modem, rather than "dongle"
2) Some people (also mostly from the US or Canada) are still under the impression that most mobile broadband users are corporate "road warriors", and have very limited awareness of the huge massmarket of consumer dongle buyers around the world.
3) The phenomenon of prepaid mobile broadband remains quite low in awareness among people "in the industry"
4) I heard of a European operator subsidising *unlocked* embedded-3G modules in notebooks sold through *retail* channels. In other words, you open the box, get a note saying something like "Congratulations! Your laptop has 3G! We're giving you a SIM and a month's access for free...." but you can still subsequently swap it and use a competitor's SIM if you decide to, after the trial. (This is unconfirmed - but it sounds to me like an extremely expensive version of AOL's old CD-in-the-PC-box promotion technique from the 1990s)